Transformer temperature measurement in situ and far eastone show the cause of the inconsistent analysis ( A)

Transformer oil gently around the temperature measurement is one of the important indexes of the safe operation of the transformer and data analysis, the temperature measurement and the accuracy of the temperature control is very important. But from all the power supply bureau of measurement technology supervision and inspection and measurement technology supervision report defects, substation transformer oil and around the temperature measurement system are widespread in situ and remote transmission shows that the phenomenon of deviation is greater than 5 ℃. So the transformer temperature measurement in situ and far eastone show inconsistent reason is what? Basically has the following kinds: 1. Temperature measurement system is the system error of the transformer temperature measuring system is composed of multiple temperature measuring element, each according to the accuracy of temperature measuring element level has corresponding the maximum permissible error, if multiple temperature measuring elements with maximum permissible error stack, can produce a large error. For example, an oil level Pt100 temperature controller output signal to the temperature transmitter, temperature transmitter output ( 4 - 20) MA to the measurement and control, measurement and control communications to the background show temperature measurement system. The oil level of the measurement range of temperature controller for ( 0 - 160). 1 ℃, accuracy. Level 5, the maximum allowable value for error of plus or minus 2. 4 ℃, the temperature transducer for measuring range ( 0 - 160). 0 ℃, and accuracy. Level 5, the maximum permissible error of plus or minus value for 0. 8 ℃, measurement and control device of non-electricity measurement range for the data acquisition channel ( 0 - 160). 0 ℃, and accuracy. Level 5, the maximum permissible error of plus or minus value for 0. 8 ℃, the maximum error of temperature measurement system can achieve + 4. 0℃。 2. Temperature measurement component damaged transformer temperature measurement system due to the measuring system of temperature measuring element damage, can lead to local and remote display great deviation. 3. Temperature measuring element output signal did not check or out-of-tolerance far transmission signal of the temperature controller are mainly Pt100, Cu50 heat resistance, thermal resistor ( 4 - 20) MA electrical signals, 0 - ( 5) Four V signal, part of the power supply bureau in checking the temperature controller didn't check out to far transmission signal. Or is on the far transmission signal calibration, but far transmission signal by the calibration error of super bad, but still use the temperature controller. Far transfer the signal of the temperature controller is to ensure that the transformer temperature measurement in situ and remote display important guarantee consistent, so to ensure that its output value and consistent with the indicated value in situ. 4. Of temperature measuring element not check part of the power supply bureau of temperature measuring system of digital display table, temperature transmitter, temperature measurement and control device of non-electricity data acquisition channel not to carry out the check, the temperature measuring element error metropolitan caused the whole measurement system error is too large. Especially for the measurement and control device, through the years, we have the transformer temperature measurement system calibration, if the computer background temperature monitoring configuration errors, will produce great error, seriously affect the temperature measurement of remote monitoring of transformer. ( To be continued. 。 。 )